This invention relates to hydraulically assisted transmission reverser units like those employed in off-road vehicles.
Off-road vehicles are generally utilized at job sites remote from a repair facility. Therefore, should a vehicle repair be necessary, substantial vehicle down time can be accumulated before a repair can be effectuated. In many cases involving worn or defectively operating major components, it is necessary to transport the vehicle from the job site to a distant repair facility. A power shift transmission reverser can represent just such a major component.
A power shift reverser includes clutch and/or brake assemblies housed within the reverser case. The clutch and brake assemblies are subject to wear degradation requiring their repair or replacement. In conventional reversers, the clutch and brake assembly cannot be serviced without totally removing the reverser from the vehicle and completely disassembling the reverser unit because of access limitation. As a result, the repair or replacement of the reverser clutch and brake assembly represents substantial vehicle down time.
The need to remove the reverser unit from the vehicle and disassemble the unit can also be predicated upon reassembly limitation. During the disassembly of a conventional reverser, it is necessary to disturb the sun pinions relative to the planetary pinions of a planetary gear assembly associated with the reverser in order to remove the clutch and/or brake assembly. Therefore, upon reassembly, it is necessary to reposition the sun pinions relative to the planetary pinions. A special case is presented when the number of sun pinion teeth is odd. In such cases, the number of relative locations in which the sun pinion will mesh properly with respective to the planetary pinions are limited, often requiring manipulation of the planetary pinion carrier to achieve a proper mesh.